Got this one from a ‘Touch For Health’ course I once took. One of the handouts was a sheet of 12 Energy Balancing exercises for when you wake up in the morning.
A number of these were geared towards encouraging the two halves of your brain to talk to one another – which helps with various brain functions, but in particular, staying in rhythm.
Apparently babies who don’t cross crawl have a tougher time as musicians later in life, because the sense of rhythm is developed by cross crawling. The movement of the left knee with the right hand, and the right knee with the left hand helps babies’ left and right brain hemispheres communicate with one another.
So when one of my groups was having difficulty keeping eighth notes synchronized, I had each singer hold the right ear with the left hand, and the left ear with the right hand – and Ta – Dah! Much more synchronized eighth notes!
Of course, as with all stage inappropriate physical tricks, the feeling of cross holding the ears needs to be incorporated into body memory during warm up, and at any time during rehearsal when synchronization needs to be worked.